Frogspawn and hammer corals losing head

[Seamazter]

Potasium is required for a low nutirent system like zeovit, or in your case vodka.
Even if this is not the cause of this problem, you should definly test your levels.
I did see some test kits at redcoral for a fair price.
Basicly if your going to dose you must test, this goes for potasium as much as it does for anything else you add to your reef.